How to Model Cooling Service Flow of Urban Parks Based on Supply-Flow-Demand Framework? A Case Study of Beijing Olympic Park

Rapid urbanization intensifies the urban heat island effect and undermines health for vulnerable communities located beyond the effective cooling reach of large parks. This study introduced a spatially supply-flow-demand framework to quantify the cooling service flow of urban park using Beijing Olympic Park as a case study. Field measurements at representative land types in the park were integrated with local parameter as inputs to model supply. To link supply with demand, we designed a grid system with cells of approximately 500 m covering 8 km*10 km area around the park, set a scenario of removing the park and compared it with the existing scenario to simulate the effect of park, so that we can qualify building-level demand. The analysis produced preliminary maps of cooling flow of Beijing Olympic Park. Results revealed that inside the park the cooling supply varied significantly by land types and seasons. Outside the park service flow of the park attenuated rapidly beyond 1 km and 1-2 km buffer zone from the park edge exhibited unmet needs of up to 7.5℃. To integrate supply and demand into a more comprehensive evaluation map, we built adjustment gap priority map and found that the southern buffer area of the park which is closer to the city center has the most urgent demand relatively. In summary, this transferable framework offers urban planners a data-driven tool for more equitable and effective green infrastructure investment.